Structural, surface and electrical of flexible nanocomposites for dielectric applications

In this work, new composite films made of polypyrrole-graphitic carbon nitride (PPy/g-C₃N₄) and polyethylene terephthalate (PET) were prepared using the polymerization chemical method. The PET/PPy/g-C₃N₄ exhibit combination of mechanical and dielectric properties, making them promising materials for applied in industry devices. The X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy mapping techniques proved that the nanocomposites were successfully fabricated. The dielectric parameters were measured by changing the PPy/g-C₃N₄ concentration in frequency range of 10 Hz to 6 MHz. The dielectric constant increased from 38.9 for PET to 426.4 for the composite PET/PPy/g-C₃N₄, and the energy density enhanced from 1.72 × 10⁻⁴ to 1.89 × 10⁻³ J/m³, while the relaxation time decreased from 4.2 × 10⁻² to 0.34 × 10⁻³s. The addition of g-C₃N₄ introduces nitrogen functionalities that improve dielectric polarization through interfacial interactions with PPy chains. The incorporation of g-C₃N₄ contributes to process the charge discharge behavior, confirming their potential for applied in flexible energy storage devices.